Sodium arsenate in the yard and garden
Moderate risk for your yardNot medical, veterinary, or professional safety advice, and not a substitute for a qualified professional — consult one. Full disclaimer →
Safety profile for Sodium arsenate relevant to people, pets, and pollinators.
What is sodium arsenate?
The IUPAC name is Trisodium arsenate dodecahydrate.
Also known as: Trisodium arsenate dodecahydrate, Disodium arsenate, Sodium arsenate, dibasic, Sodium biarsenate.
- IUPAC name
- Trisodium arsenate dodecahydrate
- CAS number
- 7778-43-0
- Molecular formula
- Na3AsO4•12H2O
- Molecular weight
- 424.04 g/mol
- SMILES
- O[As](=O)([O-])[O-].[Na+].[Na+]
- PubChem CID
- 24500
Risk for people, pets,
Moderate riskRegulatory consensus
2 regulatory and scientific bodies have classified Sodium arsenate. The classifications differ — that's the data.
| Agency | Year | Classification | Notes |
|---|---|---|---|
| EPA | — | Hazardous waste component; Maximum contaminant level 0.01 mg/L | regulated |
| IARC | 2012 | Group 1 | carcinogenic — IARC Monographs Volume(s) 23, Sup 7, 100C (2012); List of Classifications agent "Arsenic and inorganic arsenic compounds" (Group 1) — a class evaluation; Sodium arsenate is a member (sodium arsenate is an inorganic arsenic compound) and is not listed by its own name |
Regulators apply different standards of evidence — animal-data weighting, exposure-pattern assumptions, epidemiological power thresholds — which is why two scientific bodies can review the same data and reach different conclusions. The disagreement is the data.
Where your yard encounter sodium arsenate
- pesticide production
- herbicide manufacturing
- wood preservatives (historically)
- laboratory reagent
Safer alternatives
Lower-risk approaches that achieve a similar outcome to Sodium arsenate:
-
Monosodium phosphate
Trade-offs: Lower biocidal efficacy. Phosphate runoff causes eutrophication.Relative cost: 0.5×
-
Copper-based wood preservatives (ACQ, CA-C)
Trade-offs: More corrosive to fasteners. Requires stainless steel or hot-dip galvanized hardware.Relative cost: 1.3×
Frequently asked questions
What products contain sodium arsenate?
Sodium arsenate appears in: pesticide production; herbicide manufacturing; wood preservatives (historically).
Why do regulators disagree about sodium arsenate?
Sodium arsenate has been classified by 2 agencies including EPA, IARC, with differing conclusions. Regulators apply different standards of evidence (animal data weighting, exposure-pattern assumptions, epidemiological power thresholds), which is why two scientific bodies can review the same data and reach different conclusions. See the regulatory consensus table on this page for the full picture.
See Sodium arsenate in the outdoor app
Look up products containing sodium arsenate, compare to alternatives, and explore the full data record.
Open in outdoor View raw API dataReference data, not professional advice. Aggregates publicly available regulatory and scientific data; not a substitute for veterinary, medical, legal, or regulatory advice. Why we built ALETHEIA →